This application relates to structural concepts for cooling a gas turbine engine exhaust duct.
Gas turbine engines are known, and typically include a compressor compressing air and delivering it into a combustor section. A fan delivers a portion of its airflow into the compressor, and also another portion into a bypass duct where it is utilized to provide thrust for the engine.
The air in the combustion section is mixed with fuel and ignited. Products of this combustion pass downstream over turbine rotors. Downstream of the turbine rotors, there may be an augmentor in some gas turbine engines. The products of combustion and the bypass air all leave the gas turbine engine through an exhaust duct. The exhaust duct may become quite hot, and thus cooling schemes are known.
One known type of exhaust duct mechanically connects a heat resistant liner facing a hot combustion gas flow to an outer exhaust wall. A space between the liner and the wall is provided with cooling airflow from the fan bypass air.
The exhaust duct experiences a number of stresses and strains along its length, and the mechanical connection of the liner in the prior art has raised some challenges, both with regard to the function and as to the complex construction.